The Three-Body Problem

Von Neumann pointed to the gigantic human circuit below the pyramid and began to explain, “Your Imperial Majesty, we have named this computer Qin I. Look, there in the center is the CPU, the core computing component, formed from your five best divisions. By referencing this diagram, you can locate the adders, registers, and stack memory. The part around it that looks highly regular is the memory. When we built that part, we found that we didn’t have enough soldiers. But luckily, the work done by the elements in this component is the simplest, so we trained each soldier to hold more colored flags. Each man can now complete the work that initially required twenty men. This allowed us to increase the memory capacity to meet the minimum requirements for running the Qin 1.0 operating system. Observe also the open passage that runs through the entire formation, and the light cavalry waiting for orders in that passage: That’s the system bus, responsible for transmitting information between the components of the whole system.

“The bus architecture is a great invention. New plug-in components, which can be made from up to ten divisions, can quickly be added to the main operation bus. This allows Qin I’s hardware to be easily expanded and upgraded. Look further still—you might have to use the telescope for this—and there’s the external storage, which we call the ‘hard drive’ at Copernicus’s suggestion. It’s formed by three million soldiers with more education than most. When you buried all those scholars alive after you unified China, it’s a good thing you saved these ones! Each of them holds a pen and a notepad, and they’re responsible for recording the results of the calculations. Of course, the bulk of their work is to act as virtual memory and store intermediate calculation results. They’re the bottleneck for the speed of computation. And, finally, the part that’s closest to us is the display. It’s capable of showing us in real time the most important parameters of the computation.”

Von Neumann and Newton carried over a large scroll, tall as a man, and spread it open before Qin Shi Huang. When they reached the scroll’s end, Wang’s chest tightened, remembering the legend of the assassin who hid a dagger in a map scroll that he then displayed to the emperor. But the imaginary dagger did not appear. Before them was only a large sheet of paper filled with symbols, each the size of a fly’s head. Packed so densely, the symbols were as dazzling to behold as the computer formation on the ground below.

“Your Imperial Majesty, this is the Qin 1.0 operating system we developed. The software for doing the calculations will run on top of it. That below”—Von Neumann pointed to the human-formation computer—“is the hardware. What’s on this paper is the software. The relationship between hardware and software is like that between the guqin zither and sheet music.”

He and Newton then spread open another scroll, just as large. “Your Imperial Majesty, this is the software for using numerical methods to solve those differential equations. After entering the motion vectors of the three suns at a particular moment obtained by astronomical observation, the software’s operation will give us a prediction for the suns’ subsequent motion at any moment in the future. Our first computation will calculate all the suns’ positions for the next two years. Each set of output values will be one hundred and twenty hours apart.”

Qin Shi Huang nodded. “Good. Begin.”

Von Neumann lifted both hands above his head and solemnly chanted: “As ordered by the great emperor, turn on the computer! System self-test!”

A row of soldiers standing halfway down the face of the pyramid repeated the order using flag signals. In a moment, the motherboard made of thirty million men seemed to turn into a lake filled with sparkling lights. Tens of millions of tiny flags waved. In the display formation closest to the base of the pyramid, a progress bar made of numerous green flags slowly advanced, indicating the percentage of the self-test that had been completed. Ten minutes later, the progress bar reached its end.

“Self-test complete! Begin boot sequence! Load operating system!”

Below, the light cavalry on the main bus that passed through the entire human-formation computer began to move swiftly. The main bus soon turned into a turbulent river. Along the way, the river fed into numerous thin tributaries, infiltrating all the modular subformations. Soon, the ripple of black and white flags coalesced into surging waves that filled the entire motherboard. The central CPU area was the most tumultuous, like gunpowder on fire.